Well from the sounds of it exchanges are going to have to abide by the travel rule regardless.
That's not set in stone. Nothing the FATF does is binding. They just pressure individual governments to implement their standards -- it often doesn't actually happen. None of the FATF member countries have even passed complying legislation yet, let alone the rest of the world. Anything that exchanges do to comply at this point is completely voluntary, not required. And then, once laws are actually passed, enforcement is another question entirely.